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Stationary fuel cells
02-JUL-2005

a snapshot of the development phase

Europe is lagging behind both North America and Japan in the development of stationary fuels cells and should be increasing its research efforts. Thomas Flower discusses the position of development work across the globe, and draws up some recommendations for the EU.

According to the European Hydrogen and Fuel Cell Technology Platform, hydrogen is envisioned to eventually become the primary fuel for the portable and transport sectors, and in the stationary electric power sector it will complement existing fossil fuels. In stationary energy applications, the real benefits of hydrogen can be exploited only with novel technologies such as fuel cells. As an energy source for fuel cells, its primary applications lie in distributed generation, but it could also become increasingly significant through its role in enhancing energy storability.

Fossil fuels are expected to remain the major options for primary power generation at least until 2030. Meanwhile, fuel cell technology can provide the means to utilize these fossil fuels at high efficiencies, and so can significantly reduce carbon dioxide emissions. If fuel cell systems could be commercially available at price levels in the range of €1000–1500/kW for larger systems, then by 2050, we would see the creation of a decentralized electricity generation infrastructure powered by a broad spectrum of renewables and clean technologies with a strong fuel cell component.

Still to be resolved, however, is exactly how hydrogen will be produced, and at what cost.

APPLICATIONS AND FUEL SOURCES FOR FUEL CELLS

Stationary fuel cells are now starting to enter the market place in a variety of applications. Fuel cells are being developed for small residential applications, larger industrial and commercial applications, and even for larger utility power plant applications. However, before fuel cells are to be available and cost-effective for central power plants, they must become more widely adopted in smaller applications. Most of the existing or near-term fuel cells use natural gas, the most widely available suitable fuel. A variety of other fuels are used as well – such as opportunity fuels including digester gas, landfill gas and syngas – and hydrogen. All this activity is paving the way for fuel cells to become a technology vital for a future hydrogen economy.

Table 1. Stationary fuel cells – status of key technologies
	PEMFC	PAFC	MCFC	SOFC
Simple-cycle electrical efficiency (net AC, LHV)	35%	40%	44%–50%	44%–50%
Simple-cycle electrical efficiency on H2 (net AC, LHV)	50%	50%	n/a – needs CO2	40%
Hybrid-cycle electrical efficiency on natural gas (net AC, LHV)	Temperature too low	Temperature too low	55%	> 60%
Performance degradation on natural gas (% per 1000 hours of operation)	High CO poisoning	> 0.5	> 0.5	> 0.1 for tubular 1–2 for planar
Potential fuels	Hydrogen (H2)	Natural gas, H2	Natural gas, H2, and opportunity fuels	Natural gas, H2, coal, gas, and opportunity fuels
Stack lifetime potential on natural gas (years)	1	5	3–5	5–10 for tubular Unknown for planar
Power rating range on natural gas	>100 kWe	200 kWe to 10 MWe	200 kWe to 10 MWe	1 kWe – 10 MWe
Current product cost (€/kWe)		~4000	4000–8000

TYPES OF FUEL CELL

Fuel cells are not a single technology. In fact, there are four major types of fuel cell which target stationary applications: proton exchange membrane fuel cell (PEMFC), phosphoric acid fuel cell (PAFC), molten carbonate fuel cell (MCFC) and solid oxide fuel cell (SOFC). They are named after their electrolyte, and each has its own set of advantages and characteristics, but none is yet commercially viable in any broad sense.

PEMFC and PAFC are low-temperature devices – they can start up quickly, but require pure hydrogen to operate, and PEMs contain a precious metal catalyst, which is expensive. Since pure hydrogen is not readily available, it is obtained instead from a less-than-perfect yet much more widely available source, natural gas.

In comparison, high-temperature fuel cells such as MCFC and SOFC, which contain a less expensive catalyst, are advantageous in being able to run on a variety of fuels. These include natural gas, opportunity fuels such as biogas and industrially produced syngas, as well as hydrogen. Notably, however, MCFC technology will not operate on hydrogen alone. (As none of the fuel cells can tolerate high levels of sulphur in their fuel, the widely available liquid fuels such as gasoline and diesel still present major challenges as they limit the fuel options at remote sites.) Other advantages of high-temperature fuel cells include higher electrical efficiencies of up to 44%–50%, greater effectiveness in cogeneration, and, especially for SOFC, longer life expectancy. High temperature also enables the fuel cells to form hybrids with generators such as gas turbines to result in much higher electrical efficiencies in the range of 60%–70%, which otherwise would be unfeasible with other technologies (see Table 1). Due to the solid phase of the electrolyte of SOFCs, the cells can be manufactured in a variety of geometries. Planar SOFCs are quite common with square or circular active surfaces stacked rather like sliced bread. Each cell has to be sealed off from its neighbour around the perimeter. In tubular stacks each cell has a more complex geometry. However, the sealing issue can be eliminated completely. This is the prime reason why tubular SOFCs have achieved high power ratings, longer run times and lower degradation rates than any other design of fuel cell running on natural gas.

Large funding is being devoted to fuel cell R&D, but only about 20% is reaching stationary applications

While fuel cells are starting to perform well, substantial R&D efforts are still required to reduce costs in order to enable broader market penetration. Low-temperature fuel cells have the advantage of high power density and rapid start-up and loadfollow, which makes them more suitable for portable and transport applications.

RESEARCH NEEDS AND PRIORITIES

For all types of fuel cell stack design, in order to improve performance, reduce costs and encourage further deployment, more research is needed to develop the balance of plant components and volume production methods. A large amount of funds are being devoted to fuel cell R&D worldwide, but only about 20% of this is reaching stationary applications. The bulk of R&D funding is devoted to PEM fuel cells and portable and transportation applications, because the average transport engine is less than 20% efficient, while the average power plant is about 35% efficient.

However, since power generation is the major use of fuel resources and the major source of pollution worldwide, stationary fuel cells should deserve a greater amount of R&D funding. R&D on fuel cells is concentrated mainly in Europe, North America and Japan. In the US, SOFC programmes now receive a major share of available funds for stationary fuel cells.

R&D IN JAPAN

With no significant fuels produced locally, Japan has been in the forefront of promoting new energy technologies and more efficient use of fuels. Japan has made a significant commitment to the fuel cell industry and to the use, development and deployment of fuel cells for automobile, residential and commercial use, with an emphasis on PEMFC and SOFC. The country has surprised the world by being the first out with hybrid and fuel cell cars and the first to develop common infrastructure for building a ‘hydrogen society’. Overall in financial year (FY) 2005, Japan will spend 284.8 billion Yen (US$2.6 billion) to address fuel cell and hydrogen infrastructure development, and the New Energy and Industrial Technology Development Organization (NEDO) will continue to invest in R&D for PEMFC and SOFC. The Millennium Programme, which has focused on 1 kW PEMFC systems, will be extended and will include SOFC for demonstration projects. Other activities in the programme include the broad-scale field testing of stationary fuel cells, marking a shift from R&D to market penetration, primarily with 1 kW PEMFC and SOFC for residential applications. A major gas company is currently sponsoring a programme for PEMFC systems with a home-builder to install and gain feedback on product performance for a three-year period. Also, a limited number of large MCFC units in niche industrial markets are being demonstrated.

R&D IN THE US AND CANADA

Developers in North America claim the technical leadership in all major fuel cell technologies, and more demonstration and pre-commercial units have been installed here than anywhere else. Stationary fuel cell technologies based on natural gas, coal and hydrogen continue to be the focus of key programmes going forward in North America. In FY 2005, the US Department of Energy (DOE) is spending US$379.1 million and National Research Canada is spending CAN$110 million (US$89 million) on materials, other advanced research and innovative concepts. Through the Solid State Energy Conversion Alliance (SECA) programme, the US DOE continues its focus on stationary fuel cells with specific emphasis on SOFC development. This programme and a new coal-based fuel cell programme have established the ambitious goal of reducing product cost to US$400/kW, and the coal programme is also considering CO₂ sequestration.

Both federal and state/provincial governments, notably California, are funding hydrogen fuel, storage and production programmes in support of a hydrogen economy. PAFC products have been on trial use for years, MCFC units are beginning to find their way into the market, and various residential units are also entering the market. The concept of distributed generation is taking hold with BCHP applications (cooling, heat and power for buildings) and systems with trigeneration capability. Fuel-cell and renewable-fuel programmes are starting to provide special funding for demonstrations projects in cogeneration and are initiating innovative funding such as tax rebates. The US DOE is also focusing effort on developing fuel cells for power generation, vehicle auxiliary power units and battlefield battery replacement applications. Energy security continues to be addressed as a strategy for on-site power generation, which fuel cells can provide.

R&D IN EUROPE

The EU is focusing its limited number of fuel cell programmes on R&D, field testing and niche commercial applications, but it lags Japan and the US in helping to establish the fuel cell and hydrogen industry. In FY 2005, the EU plans to spend €150 million on framework programmes and to take advantage of Europe-wide co-operation, but programmes in Member States, such as Germany’s BMWA ZIP (Bundesministerium fur Wirtschaft und Arbeit, Zukunfts-Investitions-Programm), have mostly had only local impact. Meanwhile, some major utilities in Germany have been carrying out MCFC and SOFC programmes and demonstrations, mostly under BMWA ZIP. There is increasing interest in biogas and renewable fuels, a niche for stationary low-temperature fuel cell systems is taking shape, and hydrogen production and infrastructure issues are being addressed mainly in Germany and Italy.

MARKET PARTICIPANTS WORLDWIDE

PAFCs, often termed the first generation of stationary fuel cells, took off in the market with a number of developers, but only two key players remain: UTC in the US and Toshiba in Japan. As for MCFCs, the so-called second-generation stationary fuel cell, the primary developers are lead by the US company FCE in partnership with MTU in Germany and Marubeni in Japan, with IHI and Ansaldo being active in Japan and Europe respectively.

Compared with other fuel cells which are confined to planar configurations, SOFC, because of its solid nature, can have two basic formats: tubular and planar. It has also attracted a large number of developers, most of which are focused on the planar format. The SOFC leader is generally recognized as Siemens, creator of the tubular technology, while companies such as MHI, Rolls-Royce, Sulzer Hexis, Delphi and Haldor Topsøe, to name just a few, are competing in tubular and planar SOFCs.

PEMFCs have come on strongly from some very small programmes a few years ago, but only a few companies are involved in electrolyte production and development, notably Du Pont, Gore and Dow. However, because of the low temperatures and other low barriers to entry, early developers such as Ballard, Plug Power, Idatech and Hydro-genics have been joined by a very large number of companies, including big names such as Hitachi, MHI, Toyota and Honda, who are involved in system and component developments for a wide variety of applications.

SUMMARY OF DEVELOPMENT

Stationary fuel cells are entering the marketplace, based on natural gas as the primary fuel and also on a variety of other hydrocarbon fuels. Not a single technology but a series of technologies, all fuel cells are environmentally friendly for electricity production and are starting to demonstrate their performance advantages. However, substantial R&D efforts are required to reduce product and manufacturing costs to enable broader market penetration. Perhaps most significantly, fuel cells are broadly seen as the first technology vital for the advent of a hydrogen economy.

European Hydrogen and Fuel Cell Technology Platform The European Hydrogen and Fuel Cell Technology Platform (HFP) is an organization aiming to facilitate and accelerate the development and deployment of cost-competitive, world-class energy systems and component technologies based on hydrogen and fuel cells for applications in transport, stationary and portable power. The Platform was established on recommendation by the European Commission’s High Level Group on Hydrogen and Fuel Cells and is steered by a high-level Advisory Council. The HFP tries to ensure a balanced and active participation of the major stakeholders (industry, scientific community, public authorities, users and civil society). It helps to develop awareness of market opportunities and energy scenarios for fuel cells and hydrogen, and to foster future co-operation both within the EU and on a global scale.

Fuel cell companies continue to require substantial amounts of capital to operate, with success by no means certain. Public funding is playing a major role in fuel cell development – as it should, since it would be unwise for governments to leave the environmental and resource conservation benefits of fuel cells solely in the hands of private companies.

North American companies are generally in the lead in stationary fuel cells, with both companies and governments providing substantial funds for continued development. Japanese companies are well positioned to take advantage of the major efforts that they and their government are placing on fuel cells, and they may already have the lead in transportation applications. While there is good work being conducted in Europe, the EU is lagging behind Japan and the US in establishing promising positions in the stationary and transport sections of the fuel cell and hydrogen industry.

RECOMMENDATIONS FOR THE EU

The EU will need to increase its support for fuel cell technologies and businesses if global players are to evolve within the community with a reduced time of market entry. Indeed, the EU research strategy for fuel cells should concentrate on developing low-cost, reliable and robust fuel cell stacks and systems. If this requires too large a budget, then the effort should at least focus on the balance of plant systems so that EU companies can have more than just a servicing role in the coming fuel cell industry. Technology transfer from research laboratories in Member States to industry should be encouraged, and intellectual property should be utilized to create industry opportunities.

Large-scale demonstration projects should be supported as a bridging function between small prototype demonstrations and the successful market entry of fuel cells. This will also help mitigate risks for early adopters of fuel cells and encourage their participation. Utilities and power distributors should especially be encouraged to deploy stationary fuel cells for further developing the electricity distribution network and for reducing emissions.

Worldwide co-operation will be necessary to open global markets for EU industries. Therefore, co-operation with non-EU partners should be part of the deployment programme to encourage the building-up of global alliances with strong EU participation.

Dr Thomas Flower is President, SWPC SFC Division, Siemens, based in Pittsburgh, US.
e-mail: Thomas.flower@siemens.com 

 

 

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